This is a randomized, double-blind, multiple-dose, placebo-controlled, parallel-group study to determine the efficacy and safety of the doses of Pregabalin compared to placebo for symptomatic relief of painful diabetic peripheral neuropathy. Diabetic peripheral neuropathy is defined as "peripheral somatic or autonomic nerve damage attributable solely to diabetes mellitus" and consists of several distinct clinical entities, including diffuse neuropathy (distal symmetrical sensorimotor polyneuropathy and autonomic neuropathy) and focal neuropathy (entrapments, mononeuropathy, plexopathy, radiculopathy, and cranial neuropathy). Painful neuropathy symptoms can accompany either the diffuse or focal neuropathies and are associated in diabetic patients not only with discomfort, but also with sleep interference, decrease in quality of life, and increase in psychosocial distress. The symptoms of diabetic neuropathy may include severe dysesthetic burning with nocturnal worsening (most ofter in the feet and ankles) and to a lesser extent in the upper extremities, cutaneous contact discomfort (allodynia), thermal hyperalgesia, paresthesias, insomnia, weight loss, anxiety, and depression. Painful diabetic neuropathy is often resistant to treatment with simple analgesics, and one of the most distressing features of diabetic neuropathy is that it may have an acute onset. It may spontaneously resolve in 6 to 10 months, although whether this is due to resolution of the neuropathy or progression to anesthesia is often difficult to determine. When neuropathic pain persists for more than 12 months, the pain usually does not resolve spontaneously and may last for many years, often interfering with normal activities and having marked impact on the patient's quality of life. There is need for effective, nonopiate treatment that can relieve the painful symptoms with minimal risk of dependence or impact onm patient's diabetes control. Drugs such as phenytoin, phenothiazine, antiarrhythmics, NSAIDs, and opiates have been used to treat painful neuropathy, with little success. Gabapentin, an anticonvulsant with a novel but not yet fully defined mechanism of action, was shown to be effective in the treatment of diabetic peripheral neuropathy; therefore, pregabalin, a more potent gabapentin-like compound, is being evaluated in this study with the objective of providing another therapeutic option in the treatment of painful diabetic neuropathy.